The £24 million acquisition of the Dutchman from rivals Arsenal has whetted the appetite for the new campaign after years of waiting for a big-name arrival at Old Trafford finally came to an end.

Just weeks ago, though, United supporters were already excited - and rightly so. Shinji Kagawa, the Japan playmaker, had been brought in from double Bundesliga champions Borussia Dortmund and excelled in pre-season.

Sir Alex Ferguson appeared to have finally brought in the creative midfielder United had needed for years, after failed approaches for the likes of Wesley Sneijder and Samir Nasri in the last two summer transfer windows.

It is unclear whether both, either, or neither of Kagawa and Van Persie will start against Everton at Goodison Park on Monday night, although the duo are expected to make their debuts over the course of proceedings against David Moyes’ men.

But, whatever happens in the 90 minutes, it is clear the arrival of Van Persie gives the manager a selection headache involving Kagawa which could remain for the rest of the season and beyond; just where will he fit in?

Sir Alex admitted after capturing Van Persie that he had not expected to sign the Dutchman earlier in the summer and it has to be questioned whether or not he would have gone through with the move for Kagawa if he knew the striker would have been arriving too.

While he occasionally deploys an extra man in midfield, Sir Alex is still a keen advocate of the 4-4-2 formation and now that he has signed Van Persie and already has star striker Wayne Rooney on his books, that is unlikely to change any time soon.

If the boss had any plans of switching from 4-4-2, he would have done so by now in past seasons and would certainly not have swooped for the 37-goal Dutch frontman this summer.

At Dortmund and in pre-season for United, Kagawa has excelled in a central attacking midfield position, slipping in between the lines and showcasing his first touch, sharp passes and keen eye for goal.

If both Van Persie and Rooney are starting the big games in attack for United though, Kagawa cannot play in his preferred position as a ‘No.10’ or centrally-based attacking midfielder if there is to be any balance in the side.

It is not impossible that Kagawa could play some games from out wide when Sir Alex changes things up, roaming and cutting inside, as he has often done for the Japan natinal team, but that is in a 4-2-3-1 and not in a 4-4-2 where wingers tracking back is an essential part of the system.

The other option could be for Kagawa to play deeper as a central midfielder in the 4-4-2, much like team-mates Paul Scholes or Michael Carrick, but he has limited experience in that position and doubts remain over his defensive capabilities and physical strength, while his passing range is shorter than the likes of Scholes.

When both Van Persie and Rooney are on the teamsheet, it does not look like the Japan international will be able to play in his preferred position.

He could still succeed and produce impressive performances over the course of his debut season but it undoubtedly gives Sir Alex a selection dilemma if he wants to play both his two major summer signings and Rooney in the same team.

"When both Van Persie & Rooney are on the teamsheet, it does not look like the Japan international will be able to play in his preferred position"

Goal.com Germany editor Francois Duchateau said: “I don't think he would be good as a typical central midfielder simply because of his defensive skills.

“He could maybe play as a wide midfielder, with the same characteristics as a No.10, rather than a traditional winger like Nani or Antonio Valencia.

“But he is not super flexible in my eyes. If you buy Kagawa, then you should buy him for the position where he is best: attacking midfield.”

The game against Everton will provide us with the first clues on Sir Alex’s tactical plan for the campaign but the Scot is set for a season of experimentation as he tries to find the perfect blend of his star players.

With the huge investment in Van Persie, Kagawa could find himself playing second fiddle to both the Dutchman and Rooney in the early stages of his Old Trafford career.

It will be up to the playmaker to make himself impossible to ignore in his preferred role and worsen what must be a serious but welcome headache for his manager.